Wind farms killing more bats than expected

Hawaiian hoary batAs wind farms statewide are killing more Hawaiian hoary bats than expected, a Maui wind farm is asking the state to increase the number of endangered bats and nenes it’s allowed to incidentally kill.

Kaheawa Wind Power II, a 21-megawatt generation facility that ascends the slopes of the West Maui Mountains above Maalaea, wants to increase its number of permitted bat fatalities from 11 to 62 adults and nene fatalities from 30 to 48 adults over the next 15 years. It has already exceeded its bat permitted fatalities.

“The proposed rates of take are expected to be minor relative to the total population of these species on Maui,” Maryland-based KWP II owner Terraform Power said in a statement, citing public records. “The mitigation measures . . . are designed to more than offset these effects and result in a net benefit to both species.”

But because research on both wind energy and bats is still evolving, setting ground rules is a tricky game for those who support both clean energy and wildlife protections.

“I think most of us who track native wildlife are concerned that these trends are starting to show up,” said Lucienne de Naie, conservation chairwoman of the Sierra Club Maui Group. “We’ve just got to know more as soon as possible to allow the wind farms and the creatures to co-exist.”

The ‘ope’ape’a or Hawaiian hoary bat is Hawaii’s only native terrestrial mammal, according to the state Department of Land and Natural Resources. The brown-and-gray furry creatures have white-tinged hair and ears, hence the name “hoary” or frosted.

Very little is known about the habitat and population of the ‘ope’ape’a, which is a subspecies of the North American hoary bat. Research suggests the solitary creature roosts among trees in areas near forests and feeds on native and non-native night-flying insects, according to the U.S. Fish and Wildlife Service.

Population estimates across the islands have ranged from hundreds to a few thousand, but this has been based on limited data. Nonetheless, the hoary bat was listed as a federal endangered species in October 1970.

KWP II is among several Hawaii wind farms that have been claiming more Hawaiian hoary bat lives than expected. According to a DLNR report, an estimated 19 bats and nine nenes have been killed at KWP II as of last June, five years into its 20-year permit.

At Kaheawa Wind Power I, higher up the slope at Maalaea and also owned by Terraform, an estimated 34 bats and 41 nenes have been killed since 2006. It’s permitted take by 2026 is 50 for bats and 60 for nene.

And Auwahi, operated by Sempra U.S. Gas & Power on the southern slopes of Haleakala, has recorded an estimated 23 bat fatalities since 2012. Its maximum take is 27 bats by 2037.

In total, Hawaii’s five wind major wind farms are allowed 180 incidental bat deaths. However, they’ve already hit 146, and most are barely five years into their 20-year permits.

As far as the company knows, all fatalities happened because of direct collisions with spinning turbines, Terraform said. Researchers aren’t sure why most bats collide with turbines, though theories include “attraction to insects caught in turbine vortices, warmth, acoustics or mistaking turbines for roost trees.”

Nene collisions are generally attributed to in-flight misjudgment. Once or twice a week, KWP II employees search the ground around the turbines for downed wildlife.

Fatalities may simply be higher than expected because people are getting better at finding them, Terraform said. Measures, such as using specially trained dogs and setting traps for animals that generally carry off the bat carcasses, also have “resulted in higher rates of detection.”

De Naie saw two possible reasons.

“One is that they totally underestimated the lethal power of these machines and the creatures can’t escape them,” de Naie said. “The other is that this is what has been happening all along, but . . . we hadn’t done very much research and didn’t know what the levels were going to be.”

Read more at The Maui News

Comments (2)

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    Save the mosquito, kill a bat!

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    Greg Alvarez


    Scientists overwhelmingly agree that climate change poses the largest threat to many of the planet’s wildlife populations, and since wind power is the biggest, fastest, cheapest way to cut harmful carbon pollution, it remains one of the most effective ways to protect them.

    That includes bats.

    While there are many significant human-caused threats to bats, ranging from cave roost disturbance and destruction, to habitat loss through deforestation, to bioaccumulation of harmful contaminants associated with fossil fuel production and other industrial activities, the wind industry has been at the forefront in taking proactive steps to protect these important animals and works extremely hard to reduce its effects on bats.

    Over the past nearly thirteen years, the U.S. wind industry worked with public and private stakeholders to better understand our impacts, sought solutions to reduce those impacts, substantially funded research and tested new technology to further reduce wind energy’s footprint.

    With the forgoing in mind, while it is true that high level of bats are impacted at some wind energy facilities, this is not the case at large percentages of the wind farms across the country, with most sites having low bat mortality rates.

    For example, soon after discovering higher than anticipated bat fatalities at several mountain top wind facilities in the Mid-Atlantic region the wind industry helped to found the Bats and Wind Energy Cooperative, whose mission is to understand the impacts of wind on bats and find solutions to reduce those impacts. The wind industry has also partnered with researchers and the Department of Energy

    Further, in 2015, voluntary best practices designed to reduce impacts on non-regulated bat species were adopted by the wind industry. Experts predict reducing turbine rotations in low-wind speed conditions during the fall migration period could reduce bat impacts up to 30 percent. “It’s a big deal. That’s a big move on their part,” said U.S. Geological Survey bat biologist Paul Cryan in response to the announcement of AWEA adopting this measure. “It’s really encouraging to hear the industry is taking steps to curtail turbines, which is the best way we know of to reduce bat fatalities.”

    The U.S. wind industry has long operated under a legacy of care, in part due to the level of pre-construction evaluation undertaken in site selection (unique to the wind industry), designed to limit impacts on wildlife and their habitats, and post-construction monitoring undertaken to evaluate if issues exist, which should be addressed through operational adjustments. While all energy generation sources have impacts, some of which are acute and affect both human health and the environment, studies have shown wind energy to have the lowest impact on wildlife and their habitats of any source of energy.

    By way of example, in a 2009 study by the New York State Energy Research and Development Authority (NYSERDA), analyzed the lifecycle impacts of the six major forms of energy generation. It found that “non-renewable electricity generation sources, such as coal and oil, pose higher risks to wildlife than renewable electricity generation sources, such as hydro and wind.”

    American wind power is also helping to combat one of the biggest threats to bats: white nose syndrome. Since the emergence of this fungal disease in 2008, the wind industry has helped fund research to combat the disease, which has decimated bat populations throughout the Northeast and Midwest.

    All forms of energy, and really all human activities, have an impact on the natural world. When the positives and negatives and weighed, it’s clear that wind power does much more good than harm to wildlife and bat populations by reducing carbon pollution. And because of its commitment to a legacy of care, the U.S. wind industry is always striving to further minimize the limited impacts it does have.

    -Greg Alvarez, American Wind Energy Association

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